Condensed Consolidated Statements of Comprehensive Earnings - Unaudited - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 27, 2015	Sep. 30, 2016	Sep. 27, 2015
Statement of Comprehensive Income [Abstract]
Net earnings (loss)	$ 3,720	$ (4,760)	$ 26,070	$ 20,607
Other comprehensive income (loss):
Changes in fair market value of derivatives, net of tax	(263)	(17)	(36)	(34)
Changes in unrealized pension cost, net of tax	898	1,336	2,753	3,299
Cumulative translation adjustment, net of tax	(164)	(1,204)	(890)	(817)
Other comprehensive income	471	115	1,827	2,448
Comprehensive earnings (loss)	$ 4,191	$ (4,645)	$ 27,897	$ 23,055

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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